Diamondbacks farm director Shaun Larkin said Monday that Lawlar is expected to miss 4-to-6 weeks after being diagnosed with a Grade 1 left hamstring strain, Nick Piecoro of The Arizona Republic reports. Triple-A Reno placed him on its 7-day injured list Monday.
Lawlar suffered the injury while legging out a triple for Reno in Saturday's game against Sacramento. While a Grade 1 strain is the least severe, it's still going to cost the top prospect at least a month of action. Lawlar has played just 11 games this season, having previously missed time following surgery to repair ligament damage in his right thumb.